Quantum Fiber speed test
Quantum Fiber (formerly CenturyLink Fiber) is symmetrical. Upload should be close to download — if it isn't, the limit is on your side of the ONT.
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Mbps
Tap Start to run the test
Press Space to start · ~25 seconds · no ads, no sign-up
Download
—Mbps
Upload
—Mbps
Ping
—ms
Jitter
—ms
Ping under load
—ms
download / upload
Bufferbloat
—
lag when busy
Consistency
—%
how steady the speed is
Packet loss
—%
Your history saved on this device only
| When | Down | Up | Ping | Loaded | Bloat | Server |
|---|
Questions about this test
What speeds should Quantum Fiber show?
Common tiers are around 500 Mbps and 940 Mbps symmetrical, with multi-gig tiers in some areas. A 940 Mbps plan tests at about 900–940 Mbps wired.
Can I use my own router with Quantum Fiber?
Yes. Most Quantum Fiber installs hand off plain Ethernet from the ONT, so your own router works. Some older CenturyLink lines need VLAN 201 tagging.
Is this affiliated with Quantum Fiber or Lumen?
No. gbps.run is independent and ad-free, and is not affiliated with any provider.
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